tire pressures?

[darock]

Anyone got a feel for how worthwhile it is to adjust tire pressures when running TIMEATTACK?

The few times I mucked about in TA, I loaded a setup I'd worked up in testing and racing. I never bothered to look at the setup at all until I was about to call it a night. Then I noticed the tire temps were quite different than I'd seen when developing and tuning the setup elsewhere.

Anybody tried adjusting in TA? see any value?

[Gutshot]

Time attack in GTR2 puts you on the track with properly warmed tires at proper pressure. Changing tire pressures in the setup screen will not effect your initial time attack start. This much I am sure of.

However, after a lap or 2 your driving will change tire pressures/temps, as normal.

While I have not done the smart thing (actually check tire temps/pressure in a systematic way, lap to lap) I think that setting tire pressure in the setup screen will have an effect the longer you drive the time attack.

Since most add on tracks start your first time attack lap too close to the start/finish line to fully get up to speed before the lap timer begins, my best laps are usually the second or third lap, and by then the tire temps are often too hot for best grip. So I use the setup screen to plug in lower pressure so my later laps have cooler tires.

It SEEMS to work, but I can't guarantee. Need someone to actually do some checking.

[David Wright]

If you skip outlap in time attack you start at "optimum" tyre temperature and pressure - your setup for tyre pressure is ignored. If you want the setups to have an effect then don't skip the outlap :)

[darock]

What are you talking about, "skip the outlap"?

I don't think there is an outlap in the TIMEATTACK in RACE07.

[darock]

Need someone to actually do some checking.

Ain't that always the case.

So I did some checking to answer my own question. In the TIME ATTACK you start out with hot tires. It appears they're hotter than they'd be if you ran any number of laps in other sessions, but that's irrelevant really.

I repeated the same test a number of times. The test was to run 2 consecutive laps in TIME ATTACK. You start out at speed as everyone who has done this in RACE07 would know. After seeing the 2nd lap time record, I hit the Esc and went to the Car Setup screens. I recorded the tire temps for all locations on all 4 tires. After doing this with a number of different starting tire pressures (and running out of patience), I then went to Single Car Practice and ran two laps. As happens in all these games, the first lap is not timed, but the 2nd one is. After seeing it record, I hit the Esc and went to the Car Setup screen and recorded those tire temps.

What I found.............
1. It appears that no matter what starting tire pressures, the TIME ATTACK temps wind up almost exactly the same after a very short time.
2. It appears that the TA tire temps wind up almost exactly as the temps wound up in the Practice session after the same amount of laps with one exception.
3. It appears the TA tire temps simply wind up about 10F hotter in the center of the tires than what temps they reach in the Practice session.

It wasn't a waste of time, but close.

I wonder what else is basically ignored in TA.

[darock]

It's interesting for one somewhat important reason.

The temps you get in TIME ATTACK wind up with the center of the tire hotter than the insides. And that doesn't seem to screw the laptime.

For example, with one setup the temps come up in a practice session as you'd wish. There is about a 10F difference outside to inside and the center is 5F difference from either in/out. But that same setup in TIME ATTACK settles into temps with the centers hottest of the three temps.

And the car runs basically the same laptimes. hhmmmmmmm

[David Wright]

What are you talking about, "skip the outlap"?

I don't think there is an outlap in the TIMEATTACK in RACE07.

My mistake, you are right. I must admit I prefer timeattack in GTR2, not only becuase you can do the outlap but also because the coloured line on the track.

The temps you get in TIME ATTACK wind up with the center of the tire hotter than the insides. And that doesn't seem to screw the laptime.

If the tyre physics is similar to GTR2, the effect of pressure on grip is smaller than the effect of temperature. If the tyres are running a bit hotter (on average) in TimeAttack this could compensate for the small effect of not being at the optimum pressure. And tyre temperature varies all the way round the track so measuring at one point won't give you the full picture.

[darock]

And tyre temperature varies all the way round the track so measuring at one point won't give you the full picture.

Yeah, but when they're 10degreesF hotter in the center you can assume they're hotter everywhere.

And if you use MoTec, you can look at the temps in the turns or in the straights etc. The example was done that way simply to use some real numbers. The averages from MoTeC give slightly different numbers but the same relationship.